1. FIELD OF INVENTION
The present invention relates generally to the field of measurement and monitoring of ultraviolet ray emitting output intensity of ultraviolet equipment and tubes. The invention specified relates particularly to wavelengths ranges within 200 to 400 nanometers.
2. DESCRIPTION OF PRIOR ART
Ultraviolet instruments have been implemented to the many uses in a wide range of applications. Requirements vary in applications such as polymerization of industrial coatings, inks and adhesives sterilization. Inspection of the printed circuit boards, non-destructive testing using fluorescent penetrated and magnetic particle techniques are examples of use. Manufacturing of printing plates, photolithographics proven for microchips, phototheropeutic treatments, sanitation & water purification and a number of other applications exist and are still evolving.
Ultraviolet applications are generally divided into three wavelengths:
Shortwave: germicidal or UV-C have wavelengths at approx 254 nm.
Midrange: UV-B have wavelengths at approx 300-312 nm.
Longwave: Blacklight, Woods or UV-A have wavelengths at 365 nm. With the wide range of applications for ultraviolet uses, the output intensity becomes an important factor. As output intensity decays, so that performance and operation of various uses are effected. Several factors can effect the output intensity of ultraviolet lamps. First as the tubes age, the output intensity will decrease. Secondly the magnetic ballast will age and can possibly effect the performance of the ultraviolet output and if filter glass is used with shorter wavelength lamps, the filter glass can solarize over time also effecting the output intensity.
3. DESCRIPTION INTENSITY READING OF ULTRAVIOLET LAMPS AND EQUIPMENT
An Ultraviolet Radiometer is an instrument that will sense the output of an ultraviolet source and through the use of a various ultraviolet sensors, measures the photocurrent directly as an output reading in watts per square centimeter. The watts are generally in milliwatts or microwatts. The indication initially was in an analog meter later giving way to digital meter readings. The prior units utilize narrow band filter on the sensors, thus requiring different sensors for the different ultraviolet wavelengths. Present design of radiometers are designed for a more specialized light measurement. The accuracy of these units are relatively high, but the cost of the units and individual sensors is also high. The units are usually equipped with range switches and the digital readout is generally 3.5 to 4 digit readout.
4. FEATURES OF THE ALL-WAVE ULTRAVIOLET MONITOR
1. The all-wave UV intensity monitor is a small self contained unit with sensors built in.
2. The all-wave UV intensity monitor will monitor all ultraviolet wavelengths with the same sensor.
3. There is no meter to indicate intensity. All monitoring is done by an elapsed time concept.
4. The cost of the all-wave UV intensity monitor is considerably lower than any other method of measuring or monitoring UV output.
5. The all-wave intensity monitor is designed as a reference device to monitor changes over time, but can be used to determine the actual output within a relative margin.
6. The all-wave UV intensity monitor is designed to be used by manual timing, but with a modified stop watch operation can be automatic.
7. The intensity measurement is determined by use of a chart using the elapsed time from start to cycle end tone. (See FIG. 1)
8. The all-wave UV intensity monitor is designed to fit in a garment pocket.
5. REFERENCES AND PRIOR ART STATEMENT
The inventors have also researched the literature and discuss the following patents:
1. U.S. Pat. No. 3,971,943 by Jeunehomme and Essad describes a specially designed transducer for monitoring exposure of human eyes and other parts of the body. The transducer design incorporates several special filters and also uses electronic circuitry to use the signal output of the transducer coupled to a digital voltmeter. The unit is designed specifically to determine the exposure level to human body parts.
2. U.S. Pat. No. 4,065,672 by Harpster discloses an ultraviolet sensor and exposure instrument designed primarily for sensing sun exposure on animals. The unit is designed primarily as a warning device for a specific wavelength and purpose and cannot determine the actual level of ultraviolet intensity.
3. U.S. Pat. No. 4,087,692 by Lecujer and Crousillac is an apparatus for measuring atomic radiation and does not involve ultraviolet wavelengths.
4. U.S. Pat. No. 4,272,679 by Blader discloses an ultraviolet sensor. This patent is for the sensor only and does not incorporate means for determining the intensity being sensed.
5. U.S. Pat. No. 4,629,896 by Bridgen discloses a design for monitoring the intensity of water sterilization systems. The unit is designed for a specific application requiring apparatus to direct the emission from a water sterilization system.
6. U.S. Pat. No. 5,107,123 by Shu discloses a design for accumulating the exposure from the sun to determine the sun tanning effect on the skin while sun bathing.